Propeller with extended drive



March 20, 1945. E. MARTIN 2,371,873

PROPELLERS WITH EXTENDED DRIVES Filed May 8, 1940 s sheets-sheet 1A I NNN -INVENTOR Erle Mar zih ATTORNEY March 20, 1945.

E. MARTIN PRoPELLERs WITH EXTENDED DRIVES Filed May 8, 1940 3 Sheets-Sheet 2 IIII 4 lIIlIllIlllIIl/llIII/Illlllllll/lllllllllll/lll ATTORNEY March 20, 1945.

PROPELLERS WITH EXTENDED DRIVES Filed May 8, 1940 3 Sheets-Sheet 3 lNvaN-roR Erle Mar tm BY Z ATTORNEY E. MARTINv 2,371,873

strumentalitiea PatentedMar. 20, 19425 2,371,373 y raorELLEa wrrn EXTENDED nEIvE Erle/Martin, West Hartford, Conn., assignor to United Aircraft Corporation, East Hartford,- Conn.,` a corporation of Delaware Application Mey s, 1940, serial No. 333,981

(ci. 11o-135.6)

- 14 Claims.

This linvention relates to improvements 'in means for supporting and driving propellers and has particular reference to an improved support.

ing and driving means for a wing mounted airplane propeller.

An object of the invention resides in the provision of improved means for supporting the propeller from some part of an airplane such as a wing and for operatively connecting the propeller with an enginesupported independently of the propeller support. l

A further object resides in the provision of a flexible driving connection between an engine and a propeller and a support for said propeller and' said driving connection.` f

A still further object resides in the provision of a support for an aircraft propeller arranged-to carry-the propeller at a spaced distance from a part of the airplane. such as a wing, said support also providing a support and container for thev operating and control accessories of a controllable-pitch constant-speed propeller..

Other objects and advantages will be more particularly pointed out hereinafter or will become apparent as the description proceeds.'

In the accompanying drawings, in which like reference numerals are used to designate similar parts throughout, there is illustrated a suitable mechanical embodiment for theDul'POSe -of disclosing the invention. The drawings, however,V

are for the purpose of illustration only and are not to be taken as limiting the invention since itwlll be apparent to those skilledin the art that various changes in the illustrated construction may be resorted to without in any way exceeding the scope of the invention.

In the drawings, i

Fig. 1 1s e sectional view of the f erwnrd portionV ofthe propeller support and the hub portion of the propeller carried thereby. Y Y Fig. 2 .is a sectional-view of the rearward portion of the propeller support. A Y

Fig. 3-is a sectional view on an enlarged scal Y on the line 3--3 of Fig. 1 of a flexible driving cou' pling incorporated in the drive between the enxine and the propeller, and' Fig.'4 is a diagrammatic view to illustrate the operation of the propeller pitchcontrolling in- BeferringtothedrawinxsindetaiLandparticula'rly to Fis. .2, the numeral il generally indicates theoutlineofanairplane'partuponwhich the'` improved support is moimtcd, the outlineillustratedbgingthatottheforwardor noseportionofanairplanewing. 'niewing Il may carry` a nacelle provided with a rigid structural wall I2 which may be suitably apertured for the projection of the nose piece Il of the independently supported vengine therethrough. A drive shaft I6 projects forwardly of the engine and is surrounded by a substantially concentric tapered metal tubular member I8 provided at its wing attached end with a reinforcing ring 20 riveted or otherwise suitably secured thereto. 'Ihe ring 20 is provided with an apertured radial flange 22 through which extend a plurality of bolts 24 for securing the end of the member I8 to the wall structure I2. 1f desired, the wall thickness of the member I8 may gradually diminish from the supporting wall I2 towards the propeller in order to diminish the structural weight of the support. At its end opposite the engine, the hollow drive shaft I6 has a spline connection with the forward end of a concentric inner shaft 30 which extends rearwardly and terminates near the 'engine connected end of the drive shaft I6. At its rearward end the hollow shaft 30 has a spline connection with a hollow inner shaft 32' which extends forwardly through the shaft 30 concentric therewith and intov the hub 34 of the propeller, generally indicated at 36,

a driving connection between the end portion of l the shaft 32 and the propeller hub being provided'V -by the spline 38. From this description it will be observed that a driving connection has been provided between the engine I4 and the propeller 3,6 and that the drive will have great exibility because of the excessive efective vlength of the three-part drive-shaft and the ability of the parts of the drive shaft to de'ect torsional-ly. 'I'his flexibility is damped by meansof a lipid friction coupling generan indicated at 40 and illustrated in section inFig.

The inner shan 32 is provided et e peint beyond the partition 6I with a splined radial enlargement 42 upon which is mounted an internally splined ring M provided with peripheral T slots into which are fitted a plurality of angularly spaced apertured vanes 46. A two part Vthe shea 32 ynud et its rearward side this ces-A ing is provided with a cylindrical extension Il which extends through theinner race ofthe bearing and has a spline connection it with" ieforwardendottheiterdrive shaft'll. The inncrrace ofthebearins!! isclampedonthe sleeve 54 between an integral annular shoulder 51 and a nut 59 screw threaded onto the sleeve, and the outer race is carried in an aperture in a transverse partition 6| secured to the end of the member I8. The outer shaft member I6 has a spline connection at its end toward the -propeller with the adjacent end of the member 30 and with the sleeve 54 and also has a locking connection with the nut 59 to retain the nut in adjusted position on the sleeve'54.

Hydraulic fluid, such as lubricating oil, is supl plied to the spaces between the vanes 46 and 50 within the casing 48 from the interior of the hollow shaft 32 through a-plurality of radial ports 58. When the vanes 46 tend to move relative to the vanes 50 the hydraulic fluid withinV the coupling will be forced through the restricted apertures in the vanes.46 from one side thereof to the other and will cause, by fluid friction, a damping of the relative movements between the vanes 45 and 50 which movements correspond to the relative movements between the forward end of the outer drive shaft I6 and the portion of lthe inner drive shaft 32 atthe location of the coupling.

angularly spaced bolts, as indicated at 64, ex-

tend' through the apertures in the flange 62, through registering apertures in the outer portion of the partition 6| and through apertures in a flange 66 provided on the rearward end of a bearing supporting nose piece 65, the flange 62, partition 6| and ange 68 being clamped together by the bolt 64in uid tight association with each other. At its forward portion the nose piece B8 is provided with a reinforced apertured end wall 10 which receives the main outboard propeller bearing 12 which rotatably supports the outer. portionof the propeller shaft 32 in the end of the nose piece. Y Y A The propeller 36 may be of the general character particularly illustrated and described in United States Patent Number 2,174,717 for Multipositlon controllable pitch propeller, issued October 3, 1939, toiFrank W. Caldwell, Erle Martin and J ohn'E. Anderson or in United States Patent No. 2,280,713, for Feathering propellers, issued April 21, 1942, by Erle Martin, John E. Anderson and Murray C. Beebe, Jr., and comprises, in general, a hub member 34 rigidly secured on the end of the drive shaft 32 and provided with radiallyextending integral arms 14 about which the holflow metal blades 16 are rotatably mounted, the blades beingsretained in operative position on the respective arms by suitable anti-friction thrust bearings each disposed between a flange on the respective blade end and an inwardly directed flange formed on a hub barrel member 16 which encloses the-hub 34 and the root ends cf the blades. A' gear member, as indicated at 18, is secured on the yroot end of each propeller blade and these blade carried gears mesh with the pitch changing gear 8|) which is rotatably mounted in a cam'member 82 rigidly' secured to the forward end of the hub member 34. vTlie'gear 80 is provided'with a cam sleeve which is concentric with the cam member 82 and a plurality of cam followers, as indicated at 84, cooperate with the cam member 82v and the cam sleeve on the gear 80 to rotate the gear 80 whenever the cam followers are moved through cam slots provided in these above mentioned cam elements. The cam followers are operated by a piston member 86 which is reciprocated by fluid pressure in a cylinder connected to the forward space of the hub member 14. Hydraulic fluid for operating the piston is led through the interior of the drive shaft 32, two passages for the double acting piston being provided by arranging a tube 88 in the drive shaft in such a manner that one passage is provided through the interior of the tube and another passage is provided through the space between the tube and the inner wall of the drive shaft.

'As the construction and operation of the type of propeller illustrated is illustrated and described in detail in the patent and applications referred to above it is thought that a further description of the propeller pitch changing mechanism is not necessary for the purposes of.

propeller from its feathered condition to its operative or constant speed control range of pitch angles. ,j

While a particular propeller construction has been illustrated in the accompanying drawings and herein briefly described, for the purpose of disclosing the invention, it is to be understood that the invention is not limited to any particular propeller construction but that other types of propellers may be used such as electrically actuated controllable pitch propellers or fixed or adjustable pitch propellers.

The partiton'Sl is provided with extensions 90 and 92 which are preferably formed integrally therewith. A speed governor 94 is mounted 'on the rearward face ofthe extension 90 and con.

trois a valve 96 operative in a bore provided in the extension 90. The governoris driven by the shaft 98 which is geared to the shaft 32 by means of the gears |08 and |82 and may include a pump A motor driven highpressure pump l|015 is mounted on the partition extension |08 and the pumps |84 and |06 are connected with the pitch changing mechanism of the propeller by means of a pair of conduits and ||2 and the oil transfer bearing ||4. From the bearing ||4 ra'- dial ports ||6 and ||8 extend through the wall of the shaft, the ports l| i6 leading to the interior of the tube 88 andthe ports ||8 leading Ato the space between the -tube 88 and-the shaft. An ,aperture |20 extends from the end of the tube 88 opposite the propeller through a check valve |22 into a closed cavity provided in the'rearward portion of the plug |24 which serves to receive the end of the tube 88 and divide the connection of the ports ||5 and H8. -From the cavity in the rearward portion of the plug apertures |26 in the plug, connect with the ports or Vapertures i8 leading to the interior of the fluid coupling 40 to provide a continuous supply of hydraulic fluid to the interior of the coupling.

The interior of the nose piece 68 serves as a reservoir for the hydraulic fluid for operating the propeller and filling the coupling 40 and, in order to retain the fluid in the interior of the nose piece, the nut 59 is provided, around its exterior, with a fluid seal |28, and the transfer bearing-H4 is extended forwardly and suitably flanged as indicated at |30 to seal the shaft 32. The bearing 12 4is provided with a seal |29 and oil return |3| and both bearings 55 and 12 may be lubricated by the fluid from the reservoir in the nose piece 68. If pressure lubrication lis desired the bearings may be connected with the outlet or relief vent of the pump |04.

. nected through a check valve |36 with an annular port |38 in the hollow drive shaft 98. A port |40 in the shaft 98 is connected through the channel ||2 withfthe interior. of the shaftl 32 surrounding the'tube 88 and a port |42 on the opposite side of the port |38 from the port |40 is connected with the interior of the tube 88 through the channel l l0.4 The slidable valvestem .|44 is provided with annular pistons so arranged that movements of the. stem towards the governor will connect the ports |38 and |40 and will con-- nect the port |42 with the annular port |46 leading. to the drain channel |46 and movement of the stem |44 away from the governor will .connect the ports |38 and |42 and connect the port |40 with the drain channel |48 through passageway |50 provided in the governor connected end of the valve stem. Since the interior of the tube 88 and the space between this tube and the shaft 32 lead to opposite sides of the pitch changing piston 86, it will be observed that the (above degovernor thereby throwing the governor 04 out of operation so that the flow of oil from the pump |52 through the channel ||2 to the pitch changing mechanism will not be interrupted by operation of the governor as the propeller slows down. This same movement of the valve plungerv |44 will connect the channel ||0 with the drain line |48 through the ports |46 sov that thev pitch changing mechanism may move freely in a direction to increase the pitch of the propeller to the feathered condition.

The outlet pressure of the governor pump |04 is controlled by a relief valve |60 to which the pump pressure is applied through a slide valve |62 operatively connected with the channels ||0 and ||2 so that the relief valve tends to maintain an outlet pressure greater than the pressure in the channels ||0 or H2 by the-amount of the resistance of the relief valve spring |64.

For a more detailed description of the constant speed and feathering control shown in Fig. 4 ref-v mechanism shown but not claimed in this application are claimed in co-pending U. S. applica- The `motor driven high pressure pump |06 is" connected with the interior of the reservoir by -aninlet channel |52 and this pump has an outlet channel |54 which leads to the port |38 in the governor drive shaft 98. l When it isdesired to feather the propel-ler a switch will be closed to energize the motor of the pump |06 and this switch will simultaneously energize the solenoid gf thevsolenoid valve |54. When the high pressure pump |06 begins to'operate the high pressure fluid will actuate the check valve |36 to close off the outlet |34 ofthe pump |04 and connect the outlet |55 of the pump |52 with the channel ||2 and'through a port |53 in the check valve |36, with a branch channel |56 leading to the valve |54 which channel is connected by theA operation of the solenoid valve 54with a channel |56 leading to an annularA port |60 inthe end portion of thle'shaft 98 remote from the governor. The end-portion of the shaft 98 is closed and the high pressure fluid entering the space in the end of the hollow shaft will act against the adjacent end of the valve stem |44and hold the valve stem invits limiting positionv of movement towards the vnon serial No, 464,62'1

If desired the forward portion of the propeller support may be covered by a streamlined sheet metal casing |66 the Vforwardend of which may be supported by means of an internal sheet metal ring structure |66 secured externally to `the end of the casing and internally to the bearing re .taining plate |10 for the bearing,12. The propeller hub may also be covered by a rotatable sheet metal spinner |12 the rearward end of which may be supported by a-sheet metal ring` member |14 connected at its outer edge to the rearward edge of the spinner and at its inner edge to the structure of the de-icing fluid distributing ring |16. In order to somewhat increase the efficiency of the propeller it may also be desirable to cover the shank portions of the blades `16 with cuff members |10 which may be formed of expanded rubber or some other suitable light weight material.

While a suitable mechanical embodiment has been illustrated in the accompanying drawings and hereinabove described f or the purpose of disclosing the invention, it is to be understood that the invention is not limited to the particular construction so illustrated and described, but that such changes in the size, shape and arrangements of the various parts may be resorted to as come within-the scope of the sub-joined claims.

Having now described the invention soy that others skilled in the art may clearly understand lfthe same, what 'it is desired to secure by Letters structural member, a transverse partition in said y hollow member, a drive shaft extending from said engine through said hollow member, through said partition, and through said outboard'bearing, a hydraulically. actuated controllable-pitch v propeller mounted on the projecting end of said drive shaft'beyond said bearing. propeller pitch Vcontrolling means mounted on said partition and completely enclosed within said hollow member beside said drive shaft, and a reservoir for hydraulic fluid .for operating said propeller having walls formed by said partition and said bearing vsupportprovided adjacentl to said propeller means within said reservoir for conducting fluid to the interior of said drive shaft including a, transfer bearing arranged so that leakage will drain into said reservoir.

2. In a propeller driven vehicle having an engine supported independently of the propellel support, a propeller support comprising a member fixed at one end to fixed structure of said vehicle, a transverse partition at the opposite end of said member from said fixed end, a bearing support secured to said member and extending outwardly from said partition, a bearing carried by said support, a drive shaft extending from said en- 'gine along said member and through said partition, said bearing support, and said bearing, an hydraulically-actuatedy controllable-pitch propeller mounted on the projecting end of said drive shaft beyond said bearing, propeller pitch coning support andreceiving its lubrication from said fluid.

3. A flexible propeller drive comprising, three concentric tubular shaft sections in which the outer section is adapted to be connected at one end to a propeller driving engine and is connected at its opposite end to the correspondingr end of the intermediate shaft section, the intermediate shaft section is connected to the corresponding end of the inner section at its' end adjacent to said one end ofV said outer section and said inner section is provided with a propeller receiving portion projecting beyond said opposite end of said outer section, and a two part huid friction damper' having one part rigidly secured to said opposite end of said outer section and the other part rigidly secured to said innersection to frictional- 1y damp torsional movements between said outer and said inner shaft sections.

4. The arrangement as set forth in claimy 3 in which all the connections between said shaft sections are torsionally positive but "completely free in a direction along the axis of said sections.

5.. 'I'he arrangement as set forth in claim 3 in which said` tubular inner shaft section receives hydraulic fluid under pressure and includes channels for conducting hydraulic fluid to the interior of said fluid friction damper.

6. In a-propeller driven vehicle having an engine `supported independently of the propellersupport, a propeller support comprising a member fixed at one end to fixed structure of said vehicle and extending outwardly therefrom, a bearing support secured to said member and extending outwardly therefrom, a drive shaftex tending from said engine along said member and through said bearing support and said bearing, a hydraulically actuated controllable pitch propeller mounted on the projecting end of said drive shaft beyond said bearing, a closed chamber adjacent said bearing for storing 'hydraulic fluid, propeller pitch controlling means utilizing said fluid to change thepropeller pitch, said drive shaft comprising a plurality of concentric overlapping shafts having their ends operatively connected to provide a continuous drive from said engine to said propeller through all of said shafts in sequence, a torsional damping devicev located in said reservoir and connecting the inner and outer of said shafts, means for conducting a portion of said hydraulic fluid to said damping device, said damping device being arranged so that leakage therefrom drains directly,r into said res-l ervoir.

7. In a propeller driven vehicle supporting an engine and a propeller independently of each other, a propeller support comprising a member fixed at one end to xed structure of said vehicle andextending outwardly therefrom, an outboard bearing, a support therefor at the outboard end of said member, a drive shaft extending from said engine along said member and throughsaid outboard bearing and said bearing support, an hydraulically actuated controllable-pitch propeller mounted on the projecting end of said drive shaft beyond said bearLng, propeller pitch controlling means mounted within 'said member, a separate hydraulic fluid supply, independent' of engine lubricating oil, for hydraulic uid'utilized by said pitch controlling means for operating said propeller, including a reservoir provided in said member adjacent said bearing, means, includingr a transfer bearing, within said reservoir for conducting the portion of said :fluid utilized by said pitch controlling means to the interior of sad drive shaft, said .transfer bearing arranged so that leakage therefrom will drain directly into said reservoir.

8. A device as' described in claim 6 in which means including a transferbearing are provided insaid reservoir for conducting fluid from said pitch controlling means to the interior of said driven shaft and in whichthe transfer bearing and said damping device are both arranged s0 that drainage therefrom drains directly into said reservoir.

9.'A device as described in claim '7 in which v the outboard bearing receives its lubrication from said fluid and is arranged so that fluid after lubricating said bearing drains directly into said reservoir.

10. A device as claimed in claim 2 including a drive shaft comprising, a plurality of concentric overlapping shafts, having one free end on the outside shaft and one free end on the inside shaft. and having their remaining ends operatively connected to provide a continuous drive connection 'from said engine to said propeller through all of said shafts in sequence and a torsional damping drive between the inner and outer of said shafts,

a transverse partition at the opposite end of said member from said fixed end,a bearing supported in said partition, a bearing support'secured t'o said member and extending outwardly from said partition, a second bearing carried bysaid support, a drive shaft extending from said engine along said member and through said partition,

said bearing support, and both said bearingaan hydraulically-actuatedv controllable-pitch propeller mounted on the projecting end of'said drive shaft beyond said bearings, propeller pitch controlling means mounted on said transverse partition within 'said member, said bearing support, said shaft, and said partition constituting a closed chamber for storing hydraulic uid, said pitch controlling means utilizing said fluid to change the propeller pitch, and said bearings being supported within said propeller support and receiving their lubrication from said fluid.

13. In a propeller driven vehicle supporting an engine anda propeller, a propeller support comprising a member extending outwardly from said vehicle and said engine, an'outboard bearing, a support therefore at the outboard end of said member, a drive shaft extending from said engine along said member and through said outboard bearing and said bearing support, an hydraulically-actuated controllable-pitch propeller mounted on the projecting end of said drive shaft beyond said bearing, a generally elongated propeller pitch controlling means wholly mounted within said member v vith its longitudinal axis generally parallel to said drive shaft, a separate hydraulic fluid supply, independent of engine lubricating oil, for hydraulic uid utilized by said pitch controlling means for operating saidv propeller, including a reservoir provided in said member adjacent said bearing and surrounding said shaft, a transfer bearing within said reservoir for conducting the portion of said uid utilized by said pitch controlling means 'to the interior of said drive shaft, atleast one end of said transfer bearing being within said reservoir so that leakage therefrom will drain directly into said reservoir.

14. In a propeller driven vehicle supporting an engine and a propeller, a propeller support comprising a member extending outwardly from said vehicle and said engine, an outboard bearing, a support therefor at the outboard end of said member, a drive shaft extending from said engine along said member and 4through said outboard bearing and said bearing support, an hydraulically-actuated controllable-pitch propeller mounted on the projecting end of said drive shaft beyond said bearing, propeller pitch controlling .means mounted within said member, a separate hydraulic fluid supply, independent of engine lubricating oil, for hydraulic iiuid utilized by said pitch controlling means for operating said propeller, including a reservoir provided in said member adjacent said bearing and surrounding said shaft, a transfer bearing within said reservoir for conducting the portion of said fluid utilized by said pitch controlling means to the in' terior of said drive shaft, at least one end of said ERLE MLARTIN. 

